Cod sursa(job #228674)

Utilizator RobybrasovRobert Hangu Robybrasov Data 7 decembrie 2008 19:00:50
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.99 kb
#include <cstdio>
#include <queue>
#include <vector>
#define N 100010

using namespace std;

int n,m,i,x,y,nod,nr,rez[N];
char E[N];
vector<int> L[N];
vector<int>::iterator it;
queue<int> C;

void bfs(int nod)
{
    E[nod]=1;
    for (C.push(nod); !C.empty(); C.pop())
        for (it=L[C.front()].begin(); it!=L[C.front()].end(); it++)
            if (!E[*it])
            {
                E[*it]=1;
                rez[*it]=1+rez[C.front()];
                C.push(*it);
            }
}

int main()
{
    freopen("bfs.in","r",stdin);
    freopen("bfs.out","w",stdout);
    scanf("%d %d %d\n",&n,&m,&nod);
    for (i=1; i<=m; i++)
    {
        scanf("%d %d\n",&x,&y);
        L[x].push_back(y);
    }
    bfs(nod);
    for (i=1; i<nod; i++)
        if (rez[i]) printf("%d ",rez[i]);
        else        printf("-1 ");
    printf("0 ");
    for (i=nod+1; i<=n; i++)
        if (rez[i]) printf("%d ",rez[i]);
        else        printf("-1 ");

    return 0;
}